Replacing back and ribs

Here's a wide open question..
What kind of cost would I be looking at to restore a bass that is all good except ribs and back.
Assumptions:
Flat back
Lower end wood maybe poplar, but carved
Varnish reasonably matches or compliments the top.

If a anyone out there has done this and could give an example cost great, or maybe could guess in terms of % cost of a build?

For a back and a complete rib garland, figure about 1/3 the cost of a new custom bass. I think that the harder part is finding somone who has the skills to build that much of a bass who does not want to just finish the rest and put their own name and label on it!